The present specification relates to an apparatus for measuring a version angle of a restored neck of a femur during a hip replacement procedure, and to a method of measuring a version angle of a restored neck of a femur of a leg of a patient during a hip replacement procedure.
Hip replacement is a surgical procedure in which the hip joint is replaced by a prosthetic implant. As part of the hip replacement procedure, the femoral head is replaced with a femoral prosthetic that includes a stem which is inserted into the medullary canal at the neck of the femur. The femoral prosthetic also includes a bearing surface, which is received within the acetabulum of the patient. The procedure may in some cases also involve inserting an acetabular cup into the acetabulum of the patient, for receiving the bearing surface of the femoral prosthetic.
It is important that the size, shape, orientation and alignment of the femoral prosthetic and the acetabulum (or acetabular cup, where one is used) are determined correctly, to ensure correct operation of the hip joint. For instance, misalignment between the femoral prosthetic and the acetabulum (or acetabular cup, where one is used) may lead to complications such as increased wear and tear of the bearing surfaces and/or unbalanced tension in the surrounding ligaments.
As part of this, it is important that the version angle of the restored neck of the femur is determined correctly for the patient in question. A typical version angle for many patients is around 15 degrees of anteversion, however this can vary between patients.